In a digital imaging device, for example a digital camera, an instant review (IR) image is the image displayed to the user immediately after the user has captured an image. The instant review image is typically a sub-sampled or reduced-resolution copy of the image captured by the user. The ability to produce and display the IR image quickly is advantageous to the user of the digital imaging device.
Currently, digital imaging devices have a time lag between when the user presses the shutter button to capture an image and when the instant review image is displayed. The time lag may be the result of a number of factors including the time required to clock the full image out of the image sensor, the time required to down-sample the image, the time required to color correct the image, and the like. Color correction may include using tone maps, white balancing the image, and the like.
The time required for each of these functions is dependent on the size of the image sensor inside the digital imaging device. The current trend is to increase the size of the image sensor. 10 and 12 mega-pixel sensors, once considered only for professional grade cameras, are now commonplace inside digital cameras aimed at the consumer market. As the image sensors become larger, the time lag between triggering an image capture, and displaying the instant review image, may become longer.